MiNi_ViPeR

Well, I've mentioned it in a couple other threads that I've been working on this little project of swapping in a 2uz 4.7 motor to my 2000 GS400 but it's finally in and running. I still have a couple of little bugs to work out but I have been driving it to & from work the last 2 days so I thought it was time for a post!

So basically the stock motor over heated while my wife was driving it. Of course she was completely oblivious to the gauges and warning lights in front of her so she drove it til it wouldn't run anymore and then pulled over. She then successfully started the car back up and drove it until it died on her again and then refused to start for her. Then she called me for help. I went to check it out and immediately new the car over heated and the motor was done. We towed it back to the house. I did a compression check and found that 4 of the 8 holes were dead! 0-15 psi compression! I pulled the heads and found this:

If you look close you can see where part of the piston melted to the cylinder wall. I checked the block w/ a straight edge and found the block was warped .005"

Now I had thought for a while that if this motor ever took a dump I'd figure out a way to put the 3uz 4.3 into my car. I just thought it would be cool to have a GS430 with the "paddle shift" option. After digging around online for some info, I stumbled across "Lextreme" and his SC470 where he used a 2uz block w/ his heads and fully built it for boost. After reading up on it I decided to attempt a swap in mine.

Since my heads would need a lot of work to rebuild (if at all possible) I decided to purchase a used motor from a 2007 GX470 that was t boned at the rear of the vehicle. This motor also has vvti and I thought it would make for a relatively straight forward swap. So far it looks like I was right. :-)

Here's the 4.7 motor being operated on.



I had to swap my original oil pans and pickup tube over to the new motor as well as some of the mounting studs, the oil filter housing and dipstick.

The motor I got was missing the intake manifold and injectors, so I swapped my originals to the new motor. The mounting studs on the 470 for the intake were longer than the 400's and the nuts bottomed out before they would secure the manifold. I got lazy here and used washers from my old head bolts to hold it down. The studs could have been swapped over instead.

I also used my original engine wire harness and PCM.

The coils on the 470 were different so I used the 400's.

The knock sensors on the 470 were also different and I believe used a stud to mount to the block. The ones from the 400 thread directly into the block so I removed the stud and swapped them over.

I used the 400's coolant crossover housings as well as the transfer tube for the heater core under the intake manifold.

I also used the 400's thermostat housing.

The exhaust manifolds were different and this 470 motor also used EGR. This was integrated in to the manifolds and the cylinder heads had small EGR ports above each exhaust port that the 400's manifolds don't cover. I had to get creative here and decided to tap the existing holes and then install a set screw to plug the hole.


Now the only thing left was the motor mount brackets. The ones from this 470 were completely different than the 400's and the ones from the 400 won't bolt up to the 4.7 block. The mounting holes are a little different. Just enough to **** ya off! Lol!

Here's a pic of the 400 mount on the 4.7 block. Only the top forward bolt was in the right spot.


So my neighbor and I got out the old stick welder and fabbed up some new motor mount brackets.

MiNi_ViPeR

Here's the 2 motors together getting worked on.


The only other thing I could have done is swap valve covers, but again I was feeling lazy. Lol. As you can see the left cover has the tall extension for adding oil. When it was all said and done it cleared the hood.



So here she is in the engine bay!
WOOT! :-) Yes it's dirty. But it sure looks like a stock motor to me. :-)

Flexus_GS

Cool and interesting swap! Would love to see some vids of it running.

ThomasGS4

iTrader: (19)

Holy smokes, this is fantastic! Also in for videos!

MiNi_ViPeR

Ha ha. I'll see what I can do on a video. :-)

Tonight I got a chance investigate some of the bugs that I mentioned. My issues are:

The car would sometimes be difficult to start and could take 2-3 tries to fire up.

I have a check engine light w/ code P0340-"cam sensor circuit bank 1"

And the worst, the car dies/stalls out at 3,000 rpms. Cruising around at lower rpms the car runs great. Very smooth, strong and My butt dyno can tell there is an improvement in torque. :-)

What I found out tonight is that the vvti camshaft sprockets are different from the 4.0 to the 4.7. I remember I did have to install the cam sensor from the 4.0 onto the 4.7 because the connector was different (3 way vs 2 way) but I didn't even notice the cam gears. Honestly, I'm surprised it even fired up to begin with lol. This wouldn't have been an issue if I was reusing the heads from the 4.0 or even just my camshafts but I didn't. The main difference is the sprocket from the 4.0 has one small tooth that the sensor reads once per revolution while the 4.7 has multiple larger teeth. It also looks like I can't just swap the sprockets either. The phaser is larger on the 4.7 than the 4.0 so the 4.0 sprocket won't fit over it. They only options I'm seeing so far is to modify one of the sprockets. I can either cut off the excess teeth on the 4.7's or grind out the center of the 4.0's. It would be nice if I could just buy one that fit, but I don't know of one that will work...

Here's some pix of what I'm talking about.
4.7-2uz

4.0-1uz


Does anyone know if the 4.3 cam sprocket is the same as the 4.0?

Zoolander

iTrader: (1)

I put some serious thought into doing this swap but skipped it in the end. It is so cool to see it in a GS, though, I haven't seen anybody do it with as much detail, yet.

angus

iTrader: (4)

I bet if you were to use the GS400 cams and cam gears everything would be fine - most likely gain power as well.

If your heads can be salvaged from the 1UZ (resurfaced) that might be the way to go.

tiger4life

iTrader: (16)

The 4.7 liter is rated for 270hp versus the 4.0 liter at 300. You have the intake on, are you going to try to get gs400 heads on there eventually? If not, it's unique but a lot of trouble to go through to be making less power. Any performance mods you have planned to make use of the extra displacement?

angus

iTrader: (4)

Actually it is rated for 260 and 306 ft lb.

But a lot of that is due to ECU tuning as well, I bet it makes more with the GS400 ECU - and yet even more with GS400 heads and / or cams.

There is little info out there about the UZ motors as far as different cam profiles, pistons etc. and power seems hard to produce - this has led me to abandon it in search of power and go for the 2JZ.

Still this is a cool project.

jadu

iTrader: (42)

I saw the 1.3UZ as well, and indeed a very cool project with the 2uz. It would be cool to see some dyno numbers especially using the 400 ecu.

MiNi_ViPeR

Yeah, it was pretty difficult to find out specs for these motors. Especially the top ends. It would be nice to know flow data/differences for the 2 heads, valve sizes, camshaft specs, etc. for comparison but I couldn't find it. If anyone has any of that info can you post it up?

From what I found online, differences are:

Displacement: 4.0L vs 4.7L
Block: aluminum vs cast iron
Compression ratio: 10.5:1 vs 10:1
Bore: 87.5mm vs 94mm (91mm in the 4.3)
Stroke: 82.5mm vs 84mm

The 07 GX470 has 323 ft lbs @ 3,400 rpm and 263 hp @ 5,400 rpm
The 00 GS400 has 310 ft lbs @ 4,000 rpm 300 hp @ 6,000 rpm

As was already stated the ecu plays a huge role in what these motors put out for power. The GS computer should help get the most out of the 4.7 motor in stock form. The heads/cams also can play a huge role. I may eventually go the route of cleaning up the GS heads and reusing them. I just kinda wanted to see what happened w/ what I have and was anxious to get it back on the road. Hell, I'd love to slap a couple of snails on this thing too...

I really wanted to just do something different and info was limited so I just dove into it to see what happens. Thanks to the info I found from Lextreme it gave me the confidence to give it a shot.

This car was my wife's for most of the time we've owned it but now I get to play with it. It's completely stock except for some staggered 20's (and now the motor) w/ 210k miles. It should be a good baseline though. :-) I'd love to put it on a dyno to just see how it compares to a stock GS4. Anyone in NorCal have a hook up? :-)

kamlung

iTrader: (8)

kudos to you...

i have both cars with 2/3UZ and i love the platform... keep the updates coming so if i ever total the GX and fry the GS4 motor, i can do the swap too...

angus

iTrader: (4)

Do you have any links to the 1.3UZ?

jadu

iTrader: (42)

Here you go: https://www.clublexus.com/forums/per...0-1-3uzfe.html

MiNi_ViPeR

Well, I finally got some time to look at my options again. Initially I thought I could modify the 2uz cam sprocket to work w/ my ecu & harness. Turns out the alignment dowels for the sprockets are in a different location on each motor. Once I figured that out I found out that there is no tooth in the right spot on the 2uz sprocket to modify to work. I would have to cut off all the existing teeth and then weld on a new tooth in the right spot to make it work. :-/ So I think you're prob right that my best/quickest option is going to be to swap cams.

This got me to look a little harder for some of the info on these 2 motors (specifically the heads). I really wanted to know if the cams were different. If they were the same my thought was that I could possibly just swap the left bank "timing tube" as it seems to be called in service info. I was able to find a good amount of info in alldata and there seems to be a good amount of differences and similarities. Here's what I found in engine specifications for my 2 motors:

Standard cam lobe height:
2uz = 41.94 to 42.04mm intake, 41.96 to 42.06mm exhaust
1uz = 42.61 to 42.71mm intake, 42.63 to 42.73mm exhaust

While I don't have info on duration and/or overlap, just the difference in lobe height specs tells me there's a significant difference between the motors.

Camshaft Journal diameter:
Same for both motors: 26.954 to 26.970 mm

Timing tube (phaser)Journal Diameter (external):
2uz = 39.955 to 39.964 mm
1uz = 39.958 to 39.964 mm (w/ green mark)
39.964 to 39.970 mm (w/ red mark)

This is promising for a cam swap. As long as I have the timing tube w/ a green mark on the face of it. I know my left bank is. I'll need to check my right bank.

Valve overall length:
Same for both motors. 95.05mm intake, 95.10mm exhaust

So, It looks like the cams do have a significant difference in lobe profiles and they should swap over nicely w/ a green marked timing tube. This could also be a poor mans cam swap for vehicles stock w/ 2uz motors. As long as the alignment pins in the intake cams for the timing tube alignment are in the same place.